CN116338294B - Power grid power failure tailing detection method and photovoltaic energy storage system applying same - Google Patents
Power grid power failure tailing detection method and photovoltaic energy storage system applying same Download PDFInfo
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- CN116338294B CN116338294B CN202310621248.9A CN202310621248A CN116338294B CN 116338294 B CN116338294 B CN 116338294B CN 202310621248 A CN202310621248 A CN 202310621248A CN 116338294 B CN116338294 B CN 116338294B
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16566—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533
- G01R19/16585—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533 for individual pulses, ripple or noise and other applications where timing or duration is of importance
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/145—Indicating the presence of current or voltage
- G01R19/155—Indicating the presence of voltage
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16533—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the application
- G01R19/16538—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the application in AC or DC supplies
- G01R19/16547—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the application in AC or DC supplies voltage or current in AC supplies
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16566—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533
- G01R19/16576—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533 comparing DC or AC voltage with one threshold
- G01R19/1658—AC voltage or recurrent signals
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/24—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to undervoltage or no-voltage
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/122—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for inverters, i.e. dc/ac converters
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
- H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/381—Dispersed generators
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/388—Islanding, i.e. disconnection of local power supply from the network
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/22—The renewable source being solar energy
- H02J2300/24—The renewable source being solar energy of photovoltaic origin
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
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Abstract
The invention discloses a power grid power-down tailing detection method and a photovoltaic energy storage system applying the same, and the method comprises the following steps: acquiring relay state information of an inverter output side of a photovoltaic energy storage system and voltage information of each phase of a power grid; judging whether the relay is attracted or not, if so, executing the next step; if not, ending; judging whether the phase voltage is greater than 0 or not by any one phase or multiple phases respectively, if so, detecting and timing the positive and negative mark positions 1 of the phase voltage; if not, detecting and timing the positive and negative sign position 0 of the phase voltage; judging whether the positive and negative signs of the phase voltage are unchanged, if so, increasing the detection timing; if not, resetting the detection timing; judging whether the detection timing is larger than a preset threshold I, if so, judging that the network side is powered down, and outputting a relay disconnection control instruction; if not, returning to judge whether the relay is attracted or not. The method has the effect of judging whether the network side is powered down or not during the wave sealing period of the inverter and preventing the wave from being re-transmitted after the inverter is sealed.
Description
Technical Field
The application relates to the technical field of photovoltaic energy storage, in particular to a power grid power failure tailing detection method and a photovoltaic energy storage system using the same.
Background
In the photovoltaic energy storage system, a PCS (power conversion system) and a photovoltaic grid-connected inverter are both important components, and are connected between a storage battery pack and a power grid (or a load), so that the device for realizing electric energy bidirectional conversion is provided; the direct current of the storage battery can be inverted into alternating current and is transmitted to a power grid or used for alternating current load; the alternating current of the power grid can be rectified into direct current to charge the storage battery.
The energy storage inversion device is applied to a grid-connected mode and a grid-off mode, wherein the grid-off mode can be called as isolated Wang Wang operation, namely (PCS) can be disconnected with a main power grid according to actual needs under the condition of meeting set requirements, and alternating current electric energy meeting the power quality requirements of the power grid is provided for local partial loads.
As shown in fig. 1, under the working condition that the inverter is not loaded and is in grid-connected operation, when the power grid is powered down, the inverter is subjected to transient wave sealing due to logic such as gradual wave current limiting, and the like, at the moment, residual electric field energy in the filter capacitor is discharged through stray loss, and the voltage waveform of the filter capacitor is in a direct-current voltage slow attenuation state; at this time, the original network side voltage protection logic cannot rapidly judge the abnormal network voltage due to the undervoltage fault, and the subsequent rapid processing logic response of the off-network switching of the inverter is affected.
Disclosure of Invention
In order to judge whether the grid side is powered down or not in the wave sealing period of the inverter and prevent the inverter from re-wave after being sealed, the application provides a power grid power failure trailing detection method and a photovoltaic energy storage system applying the same.
In a first aspect, the present application provides a power grid power failure tail detection method, which adopts the following technical scheme:
a power grid power-down tailing detection method comprises the following steps:
acquiring relay state information of an inverter output side of a photovoltaic energy storage system and voltage information of each phase of a power grid;
judging whether the relay is attracted or not, if so, executing the next step; if not, ending;
judging whether the phase voltage is greater than 0 or not by any one phase or multiple phases respectively, if so, detecting and timing the positive and negative mark positions 1 of the phase voltage; if not, detecting and timing the positive and negative sign position 0 of the phase voltage;
judging whether the positive and negative signs of the phase voltage are unchanged, if so, increasing the detection timing; if not, resetting the detection timing;
judging whether the detection timing is larger than a preset threshold I, if so, judging that the network side is powered down, and outputting a relay disconnection control instruction; if not, returning to judge whether the relay is attracted or not.
Optionally, calculating a sum Us of the voltages of the phases; judging whether Us is larger than a preset threshold value II, if so, stopping judging whether the detection timing is larger than a preset threshold value I, and outputting a phase voltage detection abnormality prompt.
Optionally, the method further comprises:
recording the power failure of the past time based on the time parameter, recording the voltage information of each phase of the time length T1 before the power failure of the past time, and generating a voltage record before the power failure;
and respectively carrying out feature recognition and extraction on the voltage record before power failure of each phase to obtain a feature distribution data set, and predicting the power failure occurrence period based on the feature distribution data set.
Optionally, the feature distribution dataset is processed with a Box-Cox transformation function, wherein the Box-Cox transformation function satisfies:
the method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>For outputting (I)>For input, & lt + & gt>Is Euler constant, ++>And (5) for manually presetting the value, determining the optimal value according to the maximum likelihood or the maximum log likelihood.
Optionally, the method further comprises:
dividing one day for 24 hours by taking T2 as a segmentation duration;
verifying the accuracy of power failure prediction in each section of T2 duration based on the power failure records of the past times;
and when the accuracy rate is higher than a preset threshold value III, outputting a relay disconnection control instruction in the next power failure prediction period corresponding to the duration of the section T2.
In a second aspect, the present application provides a photovoltaic energy storage system, which adopts the following technical scheme:
a photovoltaic energy storage system, a control module of the system loads and executes a computer program of any of the grid power loss tail detection methods described above, and is configured to:
acquiring voltage information of each phase after the relay is disconnected;
and if the voltage information of each phase accords with the preset closing condition, outputting a relay actuation control instruction.
Optionally, the control module of the system is configured to:
acquiring photovoltaic energy storage information;
and judging whether the photovoltaic energy storage information is higher than a preset threshold value IV, if so, stopping outputting a relay disconnection control instruction in a power failure prediction period.
Optionally, the control module of the system is configured to:
solving a negative sequence component of the voltage at the output side of the relay based on a formula I, wherein the formula I meets the following conditions:
the method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>、/>、/>Respectively representing phase A, phase B and phase C; />A rotation factor of 120 °;
solving a voltage zero sequence component of the output side of the relay based on a formula II, wherein the formula II meets the following conditions:
；
judgingOr->If the time parameter is larger than a preset threshold value V, marking the voltage record 1 before power failure corresponding to the time parameter; if not, recording a voltage record mark 0 before power failure corresponding to the time parameter;
summarizing the voltage records before power failure, which are marked as 1, and generating a data set of;
summarizing the voltage records before power failure marked as 0 to generate a data set no;
the feature distribution dataset is processed using a Box-Cox transform function on the dataset.
In summary, the present application includes at least one of the following beneficial technical effects: when the power-down inverter on the network side is used for sealing the wave, the inverter and the power grid can be directly disconnected in a cut-off mode, and the voltage rise of the inverter terminal caused by secondary wave generation can not be caused.
Drawings
FIG. 1 is a schematic waveform diagram of the output voltage and current of the power grid and PCS when the power grid is powered down;
FIG. 2 is a schematic of the main flow of the method of the present invention.
Detailed Description
The present application is described in further detail below in conjunction with fig. 2.
The embodiment of the application discloses a power grid power failure tailing detection method, which is applied to a photovoltaic energy storage system, and can be understood as follows: in order to timely separate connection between the photovoltaic energy storage unit and the power grid when a fault occurs in the photovoltaic energy storage system, a relay is matched.
Referring to fig. 2, the power grid power-down tailing detection method includes:
acquiring relay state information of an inverter output side of a photovoltaic energy storage system and voltage information of each phase of a power grid;
judging whether the relay is attracted or not, if so, executing the next step; if not, ending;
judging whether the phase voltage is greater than 0 or not by any one phase or multiple phases respectively, if so, detecting and timing the positive and negative mark positions 1 of the phase voltage; if not, detecting and timing the positive and negative sign position 0 of the phase voltage;
judging whether the positive and negative signs of the phase voltage are unchanged, if so, increasing the detection timing; if not, resetting the detection timing;
judging whether the detection timing is larger than a preset threshold I, if so, judging that the network side is powered down, and outputting a relay disconnection control instruction; if not, returning to judge whether the relay is attracted or not.
According to the above-mentioned, when the inverter Feng Bo is powered down at the grid side, the method can directly disconnect the inverter from the grid by adopting a shutdown mode, so that the voltage rise of the inverter terminal caused by secondary wave generation is not caused.
The state information of the relay can be determined according to a signal of a relay control end, and can also be determined by sampling current of a relay contact end; the power grid phases refer in this embodiment to three-phase power phases that can be obtained by a voltage sensor or a three-phase power monitoring and analysis chip such as BL 655. The value of the threshold one can be 15ms according to verification.
In one embodiment of the method, in order to prevent erroneous judgment and erroneous control caused by the voltage detection abnormality, the sum Us of the voltages of the phases is also calculated; judging whether Us is larger than a preset threshold value II, if so, stopping judging whether the detection timing is larger than a preset threshold value I, and outputting a phase voltage detection abnormality prompt.
The sum of the three-phase voltages is 0 according to the three-phase power principle, so Us can take on a value of 0; when it is not 0, it can be considered that the voltage detection is faulty, and Us, such as an actual device error, is considered as an error allowance of not 0.
In one embodiment of the method, the method further comprises:
recording the power failure of the past time based on the time parameter, recording the voltage information of each phase of the time length T1 before the power failure of the past time, and generating a voltage record before the power failure;
and respectively carrying out feature recognition and extraction on the voltage record before power failure of each phase to obtain a feature distribution data set, and predicting the power failure occurrence period based on the feature distribution data set.
Based on the known waveform structure of the three-phase power, the characteristic identification and extraction of the voltage record before power failure comprises the following steps: and identifying the voltage of each phase, extracting the maximum amplitude and the minimum amplitude of each period of each phase, and extracting the period number of each phase in the duration of T1, wherein T1 can be 3S or 5S, and the like, and the specific value is verified and set by staff. Summarizing the data extracted from the same phase to obtain the characteristic distribution data set.
Regarding predicting a power loss occurrence period based on the feature distribution data set, for example:
calculating the feature similarity, and if the similarity (difference) is smaller than the classification threshold value, considering the feature similarity as the same;
counting various features and the occurrence frequency of various feature combinations, and taking the highest feature and feature combination as feature data before power failure. If the current voltage information feature identification and extraction result is matched with the feature data before power failure (the similarity meets the condition), the following time length T3 is considered as the power failure occurrence period.
The above example is only one way of prediction, and it will be appreciated that the feature data may also be imported into a suitable predictive model previously built based on a neural network for training to predict the time period of occurrence.
It should be noted that in the above-mentioned feature analysis process, there is a problem that, for three-phase electricity, there is a three-phase imbalance phenomenon affected by load or the like, which causes the feature book distribution to be inclined, and affects the accuracy of prediction, so the method also uses Box-Cox transformation function to process the feature distribution data set.
The Box-Cox transform function satisfies:
the method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>For outputting (I)>For input, & lt + & gt>Is Euler constant, ++>And (5) for manually presetting the value, determining the optimal value according to the maximum likelihood or the maximum log likelihood.
In one embodiment of the method, according to the power utilization characteristics of the power grid, dividing one day by 24 hours by taking T2 as a segmentation duration; for example: t2 may be 1 hour, at which time 24 time periods are divided.
Subsequently, the accuracy of the power-down prediction in each segment of the T2 duration (per hour) is verified based on the power-down records of the past times.
And when the accuracy rate is higher than a preset threshold value three (such as 95%), outputting a relay disconnection control instruction in the next power failure prediction period corresponding to the duration of the section T2.
According to the above-mentioned knowledge, the method can calculate the prediction accuracy of each hour, and only in the period with high accuracy, the photovoltaic energy storage and the power grid can be actively disconnected in advance after the subsequent power-down period is predicted, so as to reduce the power-down influence of the power grid. The method can avoid the possibility of misjudgment of the power grid interference factors and the time period increase of a plurality of variables, and improves the accuracy of the pre-breaking of the network.
The embodiment of the application also discloses a photovoltaic energy storage system, and it can be understood that the system is provided with at least one control module.
A photovoltaic energy storage system, the control module of which loads and executes a computer program of any one of the grid power loss tail detection methods described above, and is configured to:
acquiring voltage information of each phase after the relay is disconnected;
and if the voltage information of each phase accords with the preset closing condition, outputting a relay actuation control instruction.
According to the above, if the power grid is powered down, the photovoltaic energy storage system directly turns off the connection with the power grid after the inverter is sealed, and the voltage rise of the inverter terminal caused by secondary wave generation is avoided, so that the protection function is achieved.
Because the above prediction of the power down period is found to be temporarily not hundred percent correct in practical testing, in order to not interfere with the photovoltaic energy storage too much, the control module of the system is configured to:
acquiring photovoltaic energy storage information (such as energy storage feedback of a storage battery pack);
and judging whether the photovoltaic energy storage information is higher than a threshold value IV, if so, stopping outputting a relay disconnection control instruction in a power failure prediction period.
When the local stored energy is close to overflow, the system does not actively disconnect the power grid based on a prediction result, but passively triggers and controls the relay based on detection timing, and the system is quick in response and shorter in time, so that the influence on the normal use of the photovoltaic energy storage system can be reduced as much as possible.
In one embodiment of the present system, the control module of the system is configured to:
solving a negative sequence component of the voltage at the output side of the relay based on a formula I, wherein the formula I meets the following conditions:
the method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>、/>、/>Respectively representing phase A, phase B and phase C; />A rotation factor of 120 °;
solving a voltage zero sequence component of the output side of the relay based on a formula II, wherein the formula II meets the following conditions:
；
judgingOr->If the time parameter is larger than a preset threshold value V, marking the voltage record 1 before power failure corresponding to the time parameter; if not, recording a voltage record mark 0 before power failure corresponding to the time parameter;
summarizing the voltage records before power failure, which are marked as 1, and generating a data set of;
summarizing the voltage records before power failure marked as 0 to generate a data set no;
the feature distribution dataset is processed using a Box-Cox transform function on the dataset.
According to the above, the system can judge whether the three-phase power is unbalanced based on the values of the zero sequence and the negative sequence, and the Box-Cox transformation is matched with the data set with the three-phase unbalance, so that the difficulty and the processing amount of system data analysis can be reduced.
The foregoing are all preferred embodiments of the present application, and are not intended to limit the scope of the present application in any way, therefore: all equivalent changes in structure, shape and principle of this application should be covered in the protection scope of this application.
Claims (8)
1. The utility model provides a power grid power-down tailing detection method which is characterized by comprising the following steps:
acquiring relay state information of an inverter output side of a photovoltaic energy storage system and voltage information of each phase of a power grid;
judging whether the relay is attracted or not, if so, executing the next step; if not, ending;
judging whether the phase voltage is greater than 0 or not by any one phase or multiple phases respectively, if so, detecting and timing the positive and negative mark positions 1 of the phase voltage; if not, detecting and timing the positive and negative sign position 0 of the phase voltage;
judging whether the positive and negative signs of the phase voltage are unchanged, if so, increasing the detection timing; if not, resetting the detection timing;
judging whether the detection timing is larger than a preset threshold I, if so, judging that the network side is powered down, and outputting a relay disconnection control instruction; if not, returning to judge whether the relay is attracted or not.
2. The power grid power-down tailing detection method as claimed in claim 1, wherein: calculating the sum Us of the voltages of the phases; judging whether Us is larger than a preset threshold value II, if so, stopping judging whether the detection timing is larger than a preset threshold value I, and outputting a phase voltage detection abnormality prompt.
3. The power grid power loss smear detection method according to claim 1, further comprising:
recording the power failure of the past time based on the time parameter, recording the voltage information of each phase of the time length T1 before the power failure of the past time, and generating a voltage record before the power failure;
and respectively carrying out feature recognition and extraction on the voltage record before power failure of each phase to obtain a feature distribution data set, and predicting the power failure occurrence period based on the feature distribution data set.
4. A power grid power down tailing detection method as claimed in claim 3, wherein: processing the feature distribution data set by using a Box-Cox transformation function, wherein the Box-Cox transformation function satisfies the following conditions:
the method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>For outputting (I)>For input, & lt + & gt>Is Euler constant, ++>And (5) for manually presetting the value, determining the optimal value according to the maximum likelihood or the maximum log likelihood.
5. The method for detecting power grid power loss smear according to claim 4, further comprising:
dividing one day for 24 hours by taking T2 as a segmentation duration;
verifying the accuracy of power failure prediction in each section of T2 duration based on the power failure records of the past times;
and when the accuracy rate is higher than a preset threshold value III, outputting a relay disconnection control instruction in the next power failure prediction period corresponding to the duration of the section T2.
6. A photovoltaic energy storage system, characterized by: a control module of the system loads and executes a computer program of the grid power loss smear detection method according to any one of claims 1 to 5, and is configured to:
acquiring voltage information of each phase after the relay is disconnected;
and if the voltage information of each phase accords with the preset closing condition, outputting a relay actuation control instruction.
7. The photovoltaic energy storage system of claim 6, wherein the control module of the system is configured to:
acquiring photovoltaic energy storage information;
and judging whether the photovoltaic energy storage information is higher than a preset threshold value IV, if so, stopping outputting a relay disconnection control instruction in a power failure prediction period.
8. The photovoltaic energy storage system of claim 7, wherein the control module of the system is configured to:
solving a negative sequence component of the voltage at the output side of the relay based on a formula I, wherein the formula I meets the following conditions:
the method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>、/>、/>Respectively representing phase A, phase B and phase C; />A rotation factor of 120 °;
solving a voltage zero sequence component of the output side of the relay based on a formula II, wherein the formula II meets the following conditions:
；
judgingOr->If the time parameter is larger than a preset threshold value V, marking the voltage record 1 before power failure corresponding to the time parameter; if not, recording a voltage record mark 0 before power failure corresponding to the time parameter;
summarizing the voltage records before power failure, which are marked as 1, and generating a data set of;
summarizing the voltage records before power failure marked as 0 to generate a data set no;
the feature distribution dataset is processed using a Box-Cox transform function on the dataset.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102116822A (en) * | 2010-12-30 | 2011-07-06 | 易事特电力***技术有限公司 | Method for detecting power failure of power grid for three-phase uninterruptable power supply |
| KR101299960B1 (en) * | 2013-07-22 | 2013-08-26 | 쏠라이앤에스(주) | Grid connected solar generation system |
| CN203839961U (en) * | 2014-04-04 | 2014-09-17 | 江苏鼎英电力设备有限公司 | Reactive compensation combination switch having power failure detection function |
| CN107843808A (en) * | 2017-10-17 | 2018-03-27 | 厦门科华恒盛股份有限公司 | A kind of power failure detection method and device of power network hangover |
| CN110797968A (en) * | 2019-11-06 | 2020-02-14 | 漳州科华技术有限责任公司 | Power-off prevention method and system for uninterruptible power supply and terminal equipment |
| CN114977475A (en) * | 2022-06-27 | 2022-08-30 | 北京德亚特应用科技有限公司 | Method, device and equipment for quickly switching load voltage source |
| CN115201598A (en) * | 2022-07-05 | 2022-10-18 | 固德威电源科技(广德)有限公司 | Grid angle sudden change detection and power recovery method for three-phase power grid |
| CN115825540A (en) * | 2022-11-30 | 2023-03-21 | 漳州科华技术有限责任公司 | Bypass power failure monitoring method and device and UPS system |
| WO2023039775A1 (en) * | 2021-09-16 | 2023-03-23 | 华为数字能源技术有限公司 | Photovoltaic system, relay detection method, and power source system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116243234B (en) * | 2023-05-11 | 2023-08-11 | 石家庄科林电气股份有限公司 | Power failure detection method and system of multimode assembled electric energy meter and electric energy meter |
-
2023
- 2023-05-30 CN CN202310621248.9A patent/CN116338294B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102116822A (en) * | 2010-12-30 | 2011-07-06 | 易事特电力***技术有限公司 | Method for detecting power failure of power grid for three-phase uninterruptable power supply |
| KR101299960B1 (en) * | 2013-07-22 | 2013-08-26 | 쏠라이앤에스(주) | Grid connected solar generation system |
| CN203839961U (en) * | 2014-04-04 | 2014-09-17 | 江苏鼎英电力设备有限公司 | Reactive compensation combination switch having power failure detection function |
| CN107843808A (en) * | 2017-10-17 | 2018-03-27 | 厦门科华恒盛股份有限公司 | A kind of power failure detection method and device of power network hangover |
| CN110797968A (en) * | 2019-11-06 | 2020-02-14 | 漳州科华技术有限责任公司 | Power-off prevention method and system for uninterruptible power supply and terminal equipment |
| WO2023039775A1 (en) * | 2021-09-16 | 2023-03-23 | 华为数字能源技术有限公司 | Photovoltaic system, relay detection method, and power source system |
| CN114977475A (en) * | 2022-06-27 | 2022-08-30 | 北京德亚特应用科技有限公司 | Method, device and equipment for quickly switching load voltage source |
| CN115201598A (en) * | 2022-07-05 | 2022-10-18 | 固德威电源科技(广德)有限公司 | Grid angle sudden change detection and power recovery method for three-phase power grid |
| CN115825540A (en) * | 2022-11-30 | 2023-03-21 | 漳州科华技术有限责任公司 | Bypass power failure monitoring method and device and UPS system |
Non-Patent Citations (3)
| Title |
|---|
| Zhi Li,et al..Failure Mechanism Analysis of High Resistance Grounding Fault Protection in Distribution Network.《2023 IEEE 3rd International Conference on Power, Electronics and Computer Applications (ICPECA)》.2023,第330-335页. * |
| 基于ZigBee的无线网络***的设计与实现;熊磊等;《计算机技术与发展》;第19卷(第4期);第242-245页 * |
| 市电电压缺陷快速检测技术研究与实现;杜伟;《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》(第05期);第C042-788页 * |
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